This invention generally deals with burglary resistant lock apparatus for conventional building-type doors and relates more particularly to a unique structure for denying unauthorized access to door lock means through the crevice between a door and its associated doorframe.
Unauthorized entry through locked doors is often accomplished by defeating the door's lock mechanism in any of a number of manners known by skilled intruders and burglars. Less sophisicated lock mechanisms may be defeated by introducing a thin rigid plate, such as a credit card, into the crevice between the door and its frame adjacent the lock mechanism to gain physical access to the latter. Even the most sturdy of the dead-bolt type locks may be quickly disabled by wedging a pry-bar into the door crevice adjacent the lock and then prying the door and lock away from the doorframe. Although some door mounting structural configurations include a stop member secured to the door frame which functions to limit the movement of the door to one side of the doorframe opening and also incidentally covers the door crevice, this stop member is often not an integral part of the door frame itself and may be easily pryed away, with burglary tools, to expose the door crevice. Doors mounted within doorframes having wooden doorjambs are particularly vulnerable to the unauthorized entry approach as mentioned above since the wooden frame structure yields easily under the leverage imposed through heavy metal pry-bars or the like. Consequently, there is a need in the art for a effective means of blocking the door crevice in a manner to insure that access to the door lock is denied and which may not be circumvented even through the use of burglary tools, but yet which does not interfere with the normal use of the door.
According to the present invention, a burglary resistant apparatus is adapted to be mounted on a doorjamb adjacent a door lock and comprises a first vertically elongate blocking plate, disposed over the crevice between the doorjamb and the door, which extends over marginal portions of the door as well as into a vertically extending groove within the interior of the doorjamb. A vertically elongate flange-like locking plate has one vertical edge thereof secured to the blocking plate and extends perpendicularly from the latter to form a rigid structural unit having a generally T-shaped cross section. The locking plate is secured to the doorjamb and cooperates with the edge of the blocking plate seated within the doorjamb groove to provide especially rigid mounting of the blocking plate in order to prevent dislodgement of the latter under the influence of burglary tools.
An important object of the invention is to provide burglary resistant apparatus which includes a stationary blocking plate covering the crevice between a door and its associated doorjamb and secured to the latter adjacent a door lock in order to deny unauthorized access to the door lock through the crevice.
Another object of the invention is to provide a blocking plate of the mentioned type which overlaps marginal portions of the door and extends into the interior of the doorjamb itself whereby to present a continuous flat surface area extending laterally a substantial distance on each side of the crevice in order to prevent the introduction of a pry-bar or the like into the door crevice amd to also resist penetration of burglary apparatus into the door or into the doorjamb adjacent to the door lock.
A further object of the present invention is to provide burglary resistant apparatus of the type mentioned that includes a flange-like member secured to the blocking plate which provides a means for securing the apparatus adjacent the door crevice in order to prevent unauthorized removal of the apparatus from the doorjamb for the purpose of gaining access to the door crevice and the door lock.
A still further object of the invention is to provide burglary resistant apparatus of the type described in which the flange-like member cooperates with the portion of the blocking plate which is disposed within the interior of the doorjamb in a manner to provide especially rigid mounting of the apparatus on the doorframe and thereby fortify the door lock mechanism to discourage intruders from tampering with the latter in an effort to gain unauthorized opening of the door.
Another object of the invention is to provide a flange-like member of the mentioned type which provides a locking plate for receiving a door lock element therethrough, while also providing a means of rigidly mounting the blocking plate on the doorjamb.
Other and further objects of the invention will be made clear or become apparent in the course of the following description of a preferred embodiment of the invention.